<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>返回箭头</title>
</head>

<body>
    <!--
        作者：放弃懒惰 链接：https: //www.zhihu.com/question/40149352/answer/3123033666

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    -->
    <div class="childItem">
        <div class="curvedarrow"></div>
    </div>
    <style>
        .childItem {
            /* border: 1px solid red; */
            display: block;
            width: 32px;
            height: 32px;
        }

        .curvedarrow {
            position: relative;
            width: 0;
            height: 0;
            border-top: 9px solid transparent;
            border-right: 9px solid tomato;
            transform: rotate(10deg);
        }

        .curvedarrow:after {
            position: absolute;
            top: -12px;
            left: -9px;
            width: 12px;
            height: 12px;
            content: "";
            border: 0 solid transparent;
            border-top: 3px solid tomato;
            border-radius: 20px 0 0 0;
            transform: rotate(45deg);
        }

        .curvedarrow:before {
            position: absolute;
            content: "";
            width: 20px;
            height: 30px;
            z-index: 1;
            background: white;
        }
    </style>
</body>

</html>